Method for improving efficiency in heating and cooling systems

Abstract

A method for improving efficiency in heating and cooling systems which includes the steps of providing speed and pressure monitoring devices for monitoring and measuring the operational speed (OS) and the head (H R ) of the fan or pump and providing a flow rate monitoring device for monitoring and measuring the fluid flow rate (Q) for fluid flowing through the fan or pump. The OS, H R and Q for the fan or pump would be periodically obtained from the speed and pressure monitoring devices and the flow rate monitoring device, and the operating S-value of the heating and cooling system would be determined by applying the formula S-value=H R /(Q R ) 2 , thereby obtaining a measurable single value representative of the overall efficiency of the heating and cooling system.

1 . A method for improving efficiency in HVAC systems, the HVAC system having at least one of a fan and a pump, a motor for driving the pump, at least one air handling unit (AHU), and a heating/cooling system, said method comprising the steps:
 providing speed and pressure monitoring means for monitoring and measuring the operational speed (OS) and the head (H R ) of the at least one of a fan and a pump;   providing flow rate monitoring means operatively associated with the at least one of a fan and a pump for monitoring and measuring the fluid flow rate (Q) for fluid flowing through the at least one of a fan and a pump;   periodically obtaining the OS, H R  and Q for the at least one of a fan and a pump from said speed and pressure monitoring means and said flow rate monitoring means;   determining the operating S-value of the HVAC system by applying the formula;
     S -value= H   R /( Q   R ) 2    
   thereby obtaining a measurable single value representative of the overall efficiency of the HVAC system.   
   
   
       2 . The method of  claim 1  further comprising the step of determining the S-value set point of the HVAC system, said S-value set point representing the optimum operating efficiency of the system 
   
   
       3 . The method of  claim 2  wherein said step of determining said S-value set point comprises providing the design head (H D ) and design fluid flow rate (Q D ) for the at least one of a fan and a pump in the HVAC system and entering the H D  and Q D  values into the equation: S-value set point=H D /(Q D ) 2 , thereby obtaining a value for the S-value set point for the HVAC system. 
   
   
       4 . The method of  claim 2  wherein said step of determining said S-value set point comprises the steps:
 running the at least one of a fan and a pump at its low speed limit;   measuring the fluid flow rate and head of the at least one of a fan and a pump;   determining the initial operating S-value (S 1 ) as the ratio of the head and the square of the fluid flow rate;   increasing the operational speed of the at least one of a fan and a pump approximately ten percent;   measuring the second fluid flow rate and second head of the at least one of a fan and a pump;   determining a second S-value (S 2 ) as the ratio of the second head and the square of the second fluid flow rate;   comparing S 2  to S 1  to determine S 2  is approximately five percent (5%) greater than S 1 ,   assigning S 1  the value of S 2  and repeating said increasing, measuring, determining and comparing steps if S 2  is not approximately five percent (5%) greater than S 1 ; and   setting said S-value set point as the average of S 1  and S 2  if S 2  is approximately five percent (5%) greater than S 1 .   
   
   
       5 . The method of  claim 2  further comprising the step of applying said operating S-value to optimize operation of the at least one of a fan and a pump by adjusting the operational speed (OS) of the at least one of a fan and a pump such that H R /(Q) 2  approaches said S-value set point. 
   
   
       6 . The method of  claim 2  further comprising the step of multiplying the S-value set point by a factor of α, where α is a safety factor which is a function of the fan/pump flow to prevent overloading of the fan/pump and is calculated by the formula α=(Q/Q D ) −n , where η is a constant between zero (0) and 0.5. 
   
   
       7 . A method for improving efficiency in heating and cooling systems, the heating and cooling system having at least one of a fan and a pump, a motor for driving the pump and a heating/cooling system, said method comprising the steps:
 providing speed and pressure monitoring means for monitoring and measuring the operational speed (OS) and the head (H R ) of the at least one of a fan and a pump;   providing flow rate monitoring means operatively associated with the at least one of a fan and a pump for monitoring and measuring the fluid flow rate (Q) for fluid flowing through the at least one of a fan and a pump;   periodically obtaining the OS, H R  and Q for the at least one of a fan and a pump from said speed and pressure monitoring means and said flow rate monitoring means;   obtaining an S-value set point for the HVAC system representing generally the optimum efficiency value for the HVAC system;   determining the operating S-value of the HVAC system by applying the formula;
     S -value= H   R /( Q   R ) 2    
   thereby obtaining a measurable single value representative of the overall operating efficiency of the HVAC system; and   comparing said operating S-value with said S-value set point to optimize operation of the at least one of a fan and a pump by adjusting the operational speed (OS) of the at least one of a fan and a pump such that said operating S-value (H R /(Q) 2 ) approaches said S-value set point.   
   
   
       8 . The method of  claim 7  wherein said step of determining said S-value set point comprises providing the design head (H D ) and design fluid flow rate (Q D ) for the at least one of a fan and a pump in the heating and cooling system and entering the H D  and Q D  values into the equation: S-value set point=H D /(Q D ) 2 , thereby obtaining a value for the S-value set point for the heating and cooling system. 
   
   
       9 . The method of  claim 7  wherein said step of determining said S-value set point comprises the steps:
 running the at least one of a fan and a pump at its low speed limit;   measuring the fluid flow rate and head of the at least one of a fan and a pump;   determining the initial operating S-value (S 1 ) as the ratio of the head and the square of the fluid flow rate;   increasing the operational speed of the at least one of a fan and a pump approximately ten percent;   measuring the second fluid flow rate and second head of the at least one of a fan and a pump;   determining a second S-value (S 2 ) as the ratio of the second head and the square of the second fluid flow rate;   comparing S 2  to S 1  to determine S 2  is approximately five percent (5%) greater than S 1 ,   assigning S 1  the value of S 2  and repeating said increasing, measuring, determining and comparing steps if S 2  is not approximately five percent (5%) greater than S 1 ; and   setting said S-value set point as the average of S 1  and S 2  if S 2  is approximately five percent (5%) greater than S 1 .   
   
   
       10 . The method of  claim 7  further comprising the step of multiplying the S-value set point by a factor of α, where α is a safety factor which is a function of the fan/pump flow to prevent overloading of the fan/pump and is calculated by the formula α=(Q/Q D ) −n , where η is a constant between zero (0) and 0.5.